聚变三乘积（Fusiontriple product）是可自持核聚变反应的重要判据,它利用聚变堆中核燃料的原子核数密度n、等离子体能量约束时间τ E 、燃料温度T这三个物理量来判断聚变反应堆是否能满足实现自持核聚变的能量平衡条件。本研究探讨了以 6 Li-D作为核燃料的聚变反应系统,并考虑了相对论效应对轫致辐射的影响以及能量回收效率对能量增益因子Q的影响,计算了忽略回旋辐射条件下 6 Li-D聚变反应系统产生Q=1的能量增益时的聚变三乘积(n i Tτ E =4.9×10 23 m -3 ·keV·s)。结果表明, 6 Li-D可以作为核聚变燃料实现正的能量增益,但其实现自持核聚变的点火条件相对于D-T核聚变的点火条件来说更为困难。

Nuclear astrophysics is a rapidly developing interdisciplinary field of research that has received extensive attention from the scientific community since the mid-twentieth century. Broadly, it uses the laws of extremely small atomic nuclei to explain the evolution of the universe. Owing to the complexity of nucleosynthesis processes and our limited understanding of nuclear physics in astrophysical environments, several critical astrophysical problems remain unsolved. To achieve a better understanding of astrophysics, it is necessary to measure the cross sections of key nuclear reactions with the precision required by astrophysical models. Direct measurement of nuclear reaction cross sections is an important method of investigating how nuclear reactions influence stellar evolution. Given the challenges involved in measuring the extremely low cross sections of nuclear reactions in the Gamow peak and preparing radioactive targets, indirect methods, such as the transfer reaction, coulomb dissociation, and surrogate ratio methods, have been developed over the past several decades. These are powerful tools in the investigation of, for example, neutron-capture (n, γ ) reactions with short-lived radioactive isotopes. However, direct measurement is still preferable, such as in the case of reactions involving light and stable nuclei. As an essential part of stellar evolution, these low-energy stable nuclear reactions have been of particular interest in recent years. To overcome the difficulties in measurements near or deeply within the Gamow window, the combination of an underground laboratory and high-exposure accelerator/detector complex is currently the optimal solution. Therefore, underground experiments have emerged as a new and promising direction of research. In addition, to better simulate the stellar environment in the laboratory, research on nuclear physics under laser-driven plasma conditions has gradually become a frontier hotspot. In recent years, the CIAE team conducted a series of distinctive nuclear astrophysics studies, relying on the Jinping Underground Nuclear Astrophysics platform and accelerators in Earth’s surface laboratories, including the Beijing Radioactive Ion beam Facility, as well as other scientific platforms at home and abroad. This research covered nuclear theories, numerical models, direct measurements, indirect measurements, and other novel approaches, achieving great interdisciplinary research results, with high-level academic publications and significant international impacts. This article reviews the above research and predicts future developments.

The determination of neutrino mass hierarchy is crucial for particle physics, astrophysics, and cosmology. In this work, we propose an easy-to-use method to determine the neutrino hierarchy based on core-collapse supernova (CCSN) neutrino detections. By analyzing the expected event rates of the neutrino burst at a terrestrial water Cherenkov detector, we found that the event rates predicted by the normal and inverted hierarchy models have marked differences in the neutrino energy range 10 similar to 20 MeV and the postbounce time <0.5 s. Within this specific energy and time range, the analytical relationship between the cumulative event number and proto-neutron star (PNS) baryon mass is extracted. Based on the normal and inverted hierarchy models, two different PNS masses can be inferred from this relationship by using the time profile of neutrino events. Then, the neutrino hierarchy can be determined by comparing the PNS mass inferred from the neutrino detections and the electromagnetic or gravitational-wave channels. Furthermore, the nonadiabatic part of the Mikheyev-Smirnov-Wolfenstein flavor conversions may also be quantified with this method, which would be very helpful for the studies of the explosion mechanism and nucleosynthesis of CCSNe.

The neutron-rich nuclei near doubly magic Sn-132 have attracted considerable interest in both nuclear physics and nuclear astrophysics. For the particle-hole nuclei in this region, the low-lying and high core excitations have been well described by shell model calculations using the extended pairing plus multipole-multipole force model. However, there is a significant difference between experiment and theory in the high-spin level 17(+) of Te-132. We intend to illustrate this difference through monopole interactions. For this purpose, the monopole corrections between pi(v) 0(g7/2) v1(d5/2) and pi(v)0h(11/2) are investigated in Te132-134, Sb131-133, and Sn-130. Some theoretical levels are connected to the (17(+)) state of (132) Te with the monopole correction (Mc) of Mc (vd5/2, vh11/2) and the quadruple-quadruple force between the proton and neutron, i.e., levels 3(-) (8(-)) in Sn-130, level 14(-) in Te-132, and level 23/2(-) in Sb-131. Their observations at lower energies can confirm the datum of level (17(+)) in Te-132 with an illustration of monopole effects and quadruple-quadruple force.

26Al with a half-life of 7.17x105 years is one of the most significant nuclides in & gamma;-ray astronomy and presolar grains of meteorites. Its main production mechanism in the H-burning MgAl cycle is the 25Mg(p, & gamma;)26Al reaction. In the temperature region of 0.05-0.3 GK of astrophysical interest, the astrophysical 25Mg(p, & gamma;) 26Al reaction rate is dominated by the resonant capture of several low-energy resonances. In this work, we report the results of a complete experimental investigation of the Ec.m. = 92, 130, and 189 keV resonances in the 25Mg(p , & gamma;)26Al reaction with the Jinping Underground Nuclear Astrophysics Experimental Facility. The up-dated thermonuclear 25Mg(p, & gamma; ) 26Al reaction rate is (32-39)% higher than that obtained at the Laboratory for Underground Nuclear Astrophysics around 0.07-0.09 GK, mainly due to the 32% enhancement of the 92-keV resonance strength. The astrophysical impact of our new rate on the 26Al yield in a 5 Mo low-metallicity asymptotic giant branch star is investigated, in which an increase of (45-79)% in the 26Al yield is found by adopting our new 25Mg(p, & gamma; ) 26Al rates.

$^{26}\mathrm{Al}$ with a half-life of $7.17\ifmmode\times\else\texttimes\fi{}{10}^{5}$ years is one of the most significant nuclides in $\ensuremath{\gamma}$-ray astronomy and presolar grains of meteorites. Its main production mechanism in the $\mathrm{H}$-burning MgAl cycle is the $^{25}\mathrm{Mg}(p,\ensuremath{\gamma})^{26}\mathrm{Al}$ reaction. In the temperature region of 0.05--0.3 GK of astrophysical interest, the astrophysical $^{25}\mathrm{Mg}(p,\ensuremath{\gamma})^{26}\mathrm{Al}$ reaction rate is dominated by the resonant capture of several low-energy resonances. In this work, we report the results of a complete experimental investigation of the ${E}_{\mathrm{c}.\mathrm{m}.}=92$, 130, and 189 keV resonances in the $^{25}\mathrm{Mg}(p,\ensuremath{\gamma})^{26}\mathrm{Al}$ reaction with the Jinping Underground Nuclear Astrophysics Experimental Facility. The updated thermonuclear $^{25}\mathrm{Mg}(p,\ensuremath{\gamma})^{26}\mathrm{Al}$ reaction rate is (32--39)% higher than that obtained at the Laboratory for Underground Nuclear Astrophysics around 0.07--0.09 GK, mainly due to the 32% enhancement of the 92-keV resonance strength. The astrophysical impact of our new rate on the $^{26}\mathrm{Al}$ yield in a 5 ${\mathrm{M}}_{\ensuremath{\bigodot}}$ low-metallicity asymptotic giant branch star is investigated, in which an increase of (45--79)% in the $^{26}\mathrm{Al}$ yield is found by adopting our new $^{25}\mathrm{Mg}(p,\ensuremath{\gamma})^{26}\mathrm{Al}$ rates.

超新星是人们能看到的宇宙中最为绚丽的烟花，其爆发时释放的能量约为太阳光度的100亿倍，可以帮助科学家们看得更远。Ia超新星作为标准烛光，人们可以借助它来测量宇宙中星系间的距离。超新星爆炸也会把产生的大量重元素抛射到星际空间，成为星系化学演化的主要驱动力。此外，超新星还对银河系元素的起源、太阳系结构形成和地球生命演化至关重要。对超新星的研究有助于丰富人们对宇宙的认识，帮助我们破解宇宙膨胀、重元素产生和生命起源之谜。当前，科学家们预测下一个超新星将随时爆发，研究人员正为观测即将爆发的超新星做充分准备。

A new Hamiltonian is established for the particle nuclei near 132Sn by including both core excitations and neutron intruder orbit i13/2. In this Hamiltonian, the two-body force strengths and monopole terms are determined by the data in 133Sn, 134Sn, 133Sb, 134Sb, 134Te, 135Te, and 135I. According to this interaction, the level spectra and electromagnetic transitions are described well in the model space including six proton orbits (0g9/2, 0g7/2, 1d5/2, 1d3/2, 2s1/2, 0h11/2), and eight neutron orbits (1d3/2, 0h11/2, 1 f7/2, 2p3/2, 2p1/2, 0h9/2, 1 f5/2, 0i13/2). This work shows that the neutron intruder orbit i13/2 is necessary to describe particle nuclei near 132Sn. The configuration including orbit i13/2 forms a spin-trap structure and wins the competition of the lowest states at level 13/2+ in 137,139Te. Spin-trap structures are also existed in levels 2- and 9-in 136,138Te. Due to the decay block by spin-trap structures, these states are predicted as good isomers.

The p-nuclei are supposed to be produced in different astrophysical processes, such as rapid-proton capture, photonuclear reaction, and neutrino-induced reaction. To date, their abundance cannot be reasonably explained. In the present work, the cross sections of the 74 Ge ( ν e , e − ) 74 As reaction are calculated with the theoretical and experimental B (GT) values, respectively. The abundance ratios between 74 Se and 74 Ge produced from the neutrino process ( ν -process) are estimated based on the simple hypothesis for core-collapse supernova explosions. The results show that the upper limit of the 74 Se and 74 Ge abundance ratio resulting from the ν -process is about 36% of the value in the solar system.

The ^{13}C(α,n)^{16}O reaction is the main neutron source for the slow-neutron-capture process in asymptotic giant branch stars and for the intermediate process. Direct measurements at astrophysical energies in above-ground laboratories are hindered by the extremely small cross sections and vast cosmic-ray-induced background. We performed the first consistent direct measurement in the range of E_{c.m.}=0.24 to 1.9 MeV using the accelerators at the China Jinping Underground Laboratory and Sichuan University. Our measurement covers almost the entire intermediate process Gamow window in which the large uncertainty of the previous experiments has been reduced from 60% down to 15%, eliminates the large systematic uncertainty in the extrapolation arising from the inconsistency of existing datasets, and provides a more reliable reaction rate for the studies of the slow-neutron-capture and intermediate processes along with the first direct determination of the alpha strength for the near-threshold state.

The ^{13}C(α,n)^{16}O reaction is the main neutron source for the slow-neutron-capture process in asymptotic giant branch stars and for the intermediate process. Direct measurements at astrophysical energies in above-ground laboratories are hindered by the extremely small cross sections and vast cosmic-ray-induced background. We performed the first consistent direct measurement in the range of E_{c.m.}=0.24 to 1.9 MeV using the accelerators at the China Jinping Underground Laboratory and Sichuan University. Our measurement covers almost the entire intermediate process Gamow window in which the large uncertainty of the previous experiments has been reduced from 60% down to 15%, eliminates the large systematic uncertainty in the extrapolation arising from the inconsistency of existing datasets, and provides a more reliable reaction rate for the studies of the slow-neutron-capture and intermediate processes along with the first direct determination of the alpha strength for the near-threshold state.

The core collapses of massive stars at the ends of their lives will produce powerful streams of neutrinos, which provide an important contribution to the 26 Al yield during the explosion stage. In this work, the contribution of the process 26 Mg ( ν e , e − ) 26 Al to the radioactive 26 Al in the Milky Way is studied based on a simple model. By combining the calculation of the neutrino-nucleus cross section and some hypotheses about core-collapse supernova explosions, the ratio of 26 Al and 26 Mg of the ν e -process is estimated. An analytical relationship between the 26 Mg yield and the initial mass and metallicity of massive stars is then obtained, making it easy to estimate the 26 Mg and 26 Al yields analytically. Due to the simplicity of the model, we can move away from complex calculations and into a careful study of the effects of some important factors, such as the radius of the O/Ne shell, the shock velocity, the neutrino spectrum, the Galactic mass and metallicity distribution, and so on. The uncertainties of the 26 Al yield contributed from these factors are discussed in detail. This study will facilitate an intuitive understanding of the buried implicit assumptions in previous studies.

The 25Mg(p,γ)26Al reaction plays an important role in the study of cosmic 1.809 MeV γ-ray as a signature of ongoing nucleosynthesis in the Galaxy.At astrophysical temperature around 0.1 GK,the 25Mg(p,γ)26Al reaction rates are dominated by the 92 keV resonance capture process.We report a precise measurement of the 92 keV 25Mg(p,γ)26Al resonance in the day-one experiment at Jinping Underground Nuclear Astrophysics experiment (JUNA) facility in the China Jinping Underground Laboratory (CJPL).The reso-nance strength and ground state feeding factor are determined to be 3.8±0.3 ×10-10 eV and 0.66 ± 0.04,respectively.The results are in agreement with those reported in the previous direct under-ground measurement within uncertainty,but with significantly reduced uncertainties.Consequently,we recommend new 25Mg(p,γ)26Al reaction rates which are by a factor of 2.4 larger than those adopted in REACLIB database at the temperature around 0.1 GK.The new results indicate higher production rates of 26gAl and the cosmic 1.809 MeV γ-ray.The implication of the new rates for the understanding of other astrophysical situations is also discussed.

The initial metallicity of Type Ia Supernovae (SNe Ia) progenitor that is increasing with the cosmological chemical evolution will directly lead to a decrease of the 56Ni formed during the nucleosynthesis and then a varying standard candle. The variation may seriously affect our understanding of the evolving universe. In this work, we derived the relationships between 56Ni yield and metallicity in different progenitor channels. The evolution of the cosmic mean metallicity (CMM) was used to estimate the initial metallicity of progenitors. The effect of the delay times from the birth of progenitors to their explosion was also considered. The corrections of SNe Ia luminosity were estimated and the influences of the different progenitor channels and CMM evolution rates were examined. Several important cosmological parameters were updated according to the luminosity corrections.

We propose a simple model based on the assumption that the varying fine structure constant alpha is an effect of the cosmological expansion to investigate the relation between the varying alpha and the cosmological components. For a spatially flat, homogeneous, and isotropic universe, the current proportion of cosmological components and age of the universe predicted by the model are consistent with the cosmological observations. Furthermore, the predicted current variation rate of alpha is also close to the atomic clock measurements. For the early universe, we predict a very strict constraint, which is compatible with the upper limit given by the investigations of cosmic microwave background and big bang nucleosynthesis.

In this paper we propose to use convolutional neural networks (CNNs) to improve the precision measurement of the Higgs boson-gluon effective coupling at lepton colliders. The CNN is employed to recognize the Higgs boson and a Z boson associated production process, with the Higgs boson decaying to a gluon pair and the Z boson decaying to a lepton pair at the center-of-mass energy 250 GeV and integrated luminosity 5 ab(-1). By using CNNs, the uncertainty of the effective coupling measurement can be decreased from 1.94% to about 1.28% using the PYTHIA data and from 1.82% to about 1.22% using the HERWIG data in the Monte Carlo simulation. Moreover, the performance of CNNs using different final state constituents shows that the energy distributions of the leading and subleading jets constituents play a major role in the identification and the optimal uncertainty of effective coupling using CNNs is reduced by about 35% compared to that using conventional method.

The effective coupling of Higgs boson to gluon pair is one of the most important parameters to test the Standard Model and search for the new physics beyond. In this paper, we propose several new observables based on jet energy profile to extract the effective coupling. The statistical uncertainties of the effective coupling extracted by using new observables are derived and estimated based on the simulation at the future $e^+e^-$ collider for $250$ GeV center-of-mass energy and 5 ab$^{-1}$ integrated luminosity. We found the statistical uncertainties of effective coupling via the optimized observable can reach about $1.6%$ in the channels of $Z$ boson decaying to lepton pairs and is reduced by $52%$ compared to the relevant uncertainties in conventional approach. These new observables potentially can be helpful for the measurement of effective coupling at the future $e^+e^-$ colliders.

The effective coupling of the Higgs boson to a gluon pair is one of the most important parameters to test the Standard Model and search for the new physics beyond. In this paper, we propose several new observables based on the jet energy profile to extract the effective coupling. The statistical uncertainties of the effective coupling extracted by using new observables are derived and estimated based on the simulation at the future e(+)e(-) collider for 250 GeV center-of-mass energy and 5 ab(-1) integrated luminosity. We found that the statistical uncertainties of effective coupling via the optimized observable can reach about 1.6% in the channels of a Z boson decaying to lepton pairs and is reduced by 52% compared to the relevant uncertainties in the conventional approach. These new observables potentially can be helpful for the measurement of effective coupling at future e(+)e(-) colliders.